1. Field of Invention
The present invention relates to a connector to which a signal cable is connected, and to an information processing apparatus.
2. Description of Related Art
In recent years, high performance and high-speed computation processing of a personal computer have been realized, and thus the personal computer has made a dramatic leap forward.
On the other hand, there is a problem of the temperature increase of a semiconductor device which carries out information processing in the personal computer due to the increase of amount of generated heat. As a method for suppressing the temperature rise of the semiconductor device, a cooling unit is mounted to cool the semiconductor device, and driving voltage is reduced to suppress the amount of generated heat by the semiconductor device per se which generates heat, thereby suppressing the temperature rise. Recently, it is also required to save energy, and there is a tendency that the driving voltage of the semiconductor device is further lowered.
However, if the driving voltage of the semiconductor device is lowered, malfunction is naturally prone to be generated against external noise. There are various factors causing the external noise, and as one of typical external noises, static electricity noise generated when a human body becomes charged is known. A human body or clothes come into contact with the personal computer when the computer is used or moved. Therefore, electric charge which has been accumulated as static electricity in the human body is discharged to generate static electricity noise, and the noise enters the device, so that voltage can not be supplied to the semiconductor device stably, leading to malfunction.
Especially in recent years, it is strongly required to reduce radiation noise which is radiated from the personal computer itself or a cable connected to the personal computer to outside. For this reason, in many cases, a shield cable which is shielded against the radiation noise is used as a cable connected to the personal computer (see Japanese Patent Application Laid-Open (JP-A) No. 3-155076 and Japanese Utility Model Application Laid-Open (JP-U) Nos. 3-035673 and 4-010979, for example). A connector is mounted on a side of the personal computer to which the shield cable is connected. Generally, the connector is covered with a conductive material (e.g., a metal plate) which is electrically connected to the shield for suppressing radiation noise.
However, if a connector having a structure in which its face is covered with the conductive material is mounted in the personal computer, static electricity charged in a human body or the like is prone to be discharged to the conductive material of the connector, and static electricity noise enters the device, thereby causing malfunction. That is, according to the conventional technique, if attempt is made to reduce the radiation noise, the personal computer becomes weaker against the external noise.
Such a problem of the conventional technique generally occurs not only in a personal computer but also in an information processing apparatus having a processing circuit which processes information.